American Shad and Striped Bass Spawning Migration and Habitat Selection in the Neuse River, North Carolina

Abstract

In 1952, a low-head dam was constructed at river kilometer (rkm) 225 on theNeuse River, NC, limiting migration of anadromous fishes beyond that point.In May of 1998, the dam was removed, giving improved access to 127 rkm of potential spawning habitat. We utilized radio telemetry during 1999 and 2000 to quantify the effects of dam removal on striped bass () and American shad () spawning migrations and habitat used. Locations oftelemetered striped bass and American shad were monitored continually throughout the spawning season. Spawning microhabitat utilized by American shad was compared to that available to them on the spawning grounds. No spawning habitat data werecollected for striped bass as they were widely distributed throughout the river and spawning was not observed. Of 22 telemetered American shad providing useable data,12 migrated beyond the former dam site. The average maximum distance migrated in 1999 and 2000 was 226 and 251 rkm, respectively. Of 23 striped bass providing usabledata, 15 migrated beyond the former dam site. The mean maximum distance migrated by striped bass in 1999 and 2000 was 218 and 250 rkm, respectively. In both years of this study, the primary American shad spawning grounds were located at rkm 239, 14rkm above the former dam site. Compared to available habitat, American shad used relatively coarse substrates consisting of gravel, cobble, and boulder. They also used intermediate current velocities (0.20-0.60 m/s) and depths (50-125 cm). The habitat they used after the removal of the dam, even though farther upstream, was similar to the habitat utilized prior to its removal.